1. Field of the Invention
The present invention relates to a curable (thermosetting) composition prepared by combining an unsaturated polyester resin and a polyamino compound having a plurality of secondary or primary amino moieties. The invention particularly relates to an aqueous, thermosetting composition comprising a mixture of an unsaturated polyester resin having free hydroxyl moieties and a polyamino compound, such as a polyamide, having a plurality of secondary or primary amino moieties.
2. Background
Unsaturated polyester resins are known. Such resins generally are prepared by reacting an ethylenically unsaturated dicarboxylic acid or anhydride with a polyol, typically a glycol. Curable compositions have commonly been prepared from such polyesters by blending them with an unsaturated monomer, often referred to as a reactive solvent or diluent, such as styrene. Exemplary of such technology are the following U.S. Patents: U.S. Pat. No. 3,911,048; U.S. Pat. No. 4,148,765; U.S. Pat. No. 4,233,432 and U.S. Pat. No. 4,246,367.
Aqueous polyamide resins also are known in the art. Such resins are used for example as one component in binder compositions for imparting wet strength to paper. The polyamide resins are commonly prepared by reacting a polyalkylene polyamine such as diethylenetriamine and a dicarboxylic acid such as adipic acid. For example, see Keim U.S. Pat. No. 2,926,154. By themselves these compositions are not thermosetting and in use they typically are crosslinked with epichlorohydrin. 3. Description of Prior Art
U.S. Pat. No. 3,502,602 discloses an organic solvent soluble unsaturated polyesteramide resin having terminal moieties derived from maleic acid. The resin is prepared by reacting a polymeric fatty acid or a branched polycarboxylic acid with a difunctional aminoalcohol (including a mixture of aliamines and diols) and introducing terminal maleic acid groups to react (cap) with free hydroxyl and amino moieties. The composition is thermosetting in the presence of a vinyl compound such as styrene or an acrylate and a free radical forming catalyst, particularly an organic peroxide.
U.S. Pat. No. 3,878,035 discloses a composite article made by treating a polyamide (nylon) cord or fiber with an epoxide, followed by coating the epoxide-treated polyamide with an uncured, unsaturated polyester, and then shaping and curing the coated polyamide. The unsaturated polyester is a liquid and can be made from fumaric or maleic acid and a glycol.
U.S. Pat. No. 4,066,587 describes adding a high melting point polyamide to a thermoplastic polyester to improve its flow and rheological properties.
U.S. Pat. No. 4,217,435 describes a thermoplastic hot melt adhesive made by blending a polyester resin and a polyamide resin. The polyester resin is a solid having a melting point of 90.degree. to 140.degree. C. made by reacting a mixture of dicarboxylic acids containing at least 40 mole % terephthalic acid with the remaining acid(s) selected from a long list of possible acids that includes fumaric and maleic, and a diol. The polyamide is also a solid with a melting point of 50.degree. to 200.degree. C. A nylon is preferred.
U.S. Pat. No. 4,254,254 describes a polyesteramide hot melt adhesive with a melting point of 70.degree. to 140.degree. C. made by reacting terephthalic acid, a 4-12 carbon atom aliphatic dicarboxylic acid, 1,6-hexanediol and 1,6-hexanediamine.
U.S. Pat. No. 4,373,085 discloses an adhesive composition based on certain polyesteramides. The polyesteramides are terpolymers prepared by reacting a dimerized fatty acid, a diamine, diglycolamine and a dicarboxylic acid. The dimerized fatty acids are described as polymerized, unsaturated natural and synthetic monobasic aliphatic acids of 8-22 carbon atoms.
U.S. Pat. No. 4,496,688 discloses preparing an unsaturated polyester or polyesteramide by reacting an unsaturated diacid, such as maleic acid or fumaric acid, with a polyol and/or a polyamine. The composition is cured by mixing the unsaturated polyester/polyesteramide with an ethylenically unsaturated compound such as styrene or an acrylate.
U.S. Pat. No. 4,581,093 discloses a branched hydroxyl-containing polyester resin made by reacting a diol, a triol or higher functional polyol, and dibasic aromatic and aliphatic acids. Thermosetting compositions can be prepared by adding isocyanate crosslinkers or aminoplast resins to the polyester resin.
U.S. Pat. No. 4,528,219 defines a laminated structure which uses a thermoplastic resin adhesive containing both ester and amide groups along its backbone.
U.S. Pat. No. 4,775,597 describes a UV curable composition made by mixing an ethylenically unsaturated compound such as styrene or an acrylate with a liquid adduct of an unsaturated polyester resin and a hydroxyl-containing amine having primary or secondary amino moieties. The unsaturated polyester is made by reacting an unsaturated diacid, such as maleic acid or fumaric acid, with a polyol. Linear polyesters are preferred.
U.S. Pat. No. 5,034,450 describes a thermoplastic molding composition made by blending a polyamide, a polyester elastomer and optionally a filler. The polyamide can be made from saturated or aromatic dicarboxylic acids and a diamine which is preferably a nylon. The polyester is a terpolymer of a diol, a glycol and a diacid.